• Computers and Concrete
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• v.19 no.5
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• pp.443-449
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• 2017

Taking high geothermal tunnels as background, the deformation of concrete for shotcrete use was studied by simulating hot-humid and hot-dry environments in a laboratory. The research is made up by two parts, one is the influence of two kinds of high geothermal environments on the deformation of shotcrete, and the other is the shrinkage inhibited effect of fiber materials (steel fibers, polypropylene fibers, and the mixture of both) on the concrete in hot-dry environments. The research results show that: (1) in hot and humid environments, wet expansion and thermal expansion happened on concrete, but the deformation is smooth throughout the whole curing age. (2) In hot and dry environments, the concrete suffers from shrinkage. The deformation obeys linear relationship with the natural logarithm of curing age in the first 28 days, and it becomes stable after the $28^{th}$ day. (3) The shrinkage of concrete in a hot and dry environment can be inhibited by adding fiber materials especially steel fibers, and it also obeys linear relationship with the natural logarithm of curing age before it becomes stable. However, compared with no-fiber condition, it takes 14 days, half of 28 days, to make the shrinkage become stable, and the shrinkage ratio of concrete at 180-day age decreases by 63.2% as well. (4) According to submicroscopic and microscopic analysis, there is great bond strength at the interface between steel fiber and concrete. The fiber meshes are formed in concrete by disorderly distributed fibers, which not only can effectively restrain the shrinkage, but also prevent the micro and macro cracks from extending.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.27 no.1
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• pp.28-33
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• 2017

SiC fiber can be used up to $1800^{\circ}C$ in both inert and air atmosphere without any problems such as melting and oxidation. SiC fibers can be applied to dust filtering processes as a bag filter at a high temperature above $700^{\circ}C$, which is far beyond the temperature range of currently available industrial bag filter. However the studies for the degradation of SiC fibers were still lacked in the harsh environment of steel industries and thermoelectric power plants. In this study, SiC fibers were reacted with steel dust and thermal power plant dust at a high temperature of $500^{\circ}C$ or higher, and the degraded shape of the fiber surface was observed by SEM. Also the degree of oxygen diffusion on the surface and inside of SiC fiber was analyzed by EDS.

• The Journal of Advanced Prosthodontics
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• v.6 no.4
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• pp.295-301
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• 2014

PURPOSE. Numerous methods were used to etch the fiber posts to improve its bonding to root canal dentin. Our aim was to evaluate the efficacy of 37% phosphoric acid in etching fiber posts in comparison with 24% hydrogen peroxide. MATERIALS AND METHODS. Ninety human maxillary central incisors were taken and post space preparation was done. Ninety fiber posts were taken and divided into three groups (n=30) based on the surface treatment they received ($H_3PO_4$, $H_2O_2$, distilled water) and each group was further divided (n=10) based on the time period of application (15 seconds, 30 seconds, 60 seconds). All the posts were luted into canals using Rely X UniCem-2. Each tooth was then sectioned into six slices and subjected to push out test. Data obtained was subjected to statistical analysis at P<.05. The surface topography was evaluated using scanning electron microscopy. RESULTS. Highest bond strength values were noted in 15 seconds etched phosphoric acid group and 60 seconds etched hydrogen peroxide group with no significant difference between two groups. Surface topography revealed complete epoxy layer removal with no damage to its structural integrity in those groups. CONCLUSION. $H_3PO_4$ etching for a period of 15 seconds is an effective alternative in improving the adhesion of fiber post to root dentin.

• Composites Research
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• v.23 no.3
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• pp.50-57
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• 2010

It is important to detect fibers in the sectional image of fiber reinforced cementitious composites (FRCC), since the fiber distribution is a crucial factor to predict or evaluate the mechanical performance of FRCC. In this paper, we investigated the fluorescence characteristics of Polyvinyl Alcohol (PVA) fibers, Polyethylene Terephthalate (PET) fibers, Polyethylene (PE) fibers, and Polypropylene (PP) fibers used in Engineered Cementitious Composites (ECC), which is a special kind of FRCC that incorporates synthetic fibers and exhibits extremely ductile behavior in uniaxial tension, to detect each fiber according to its type. Furthermore, optimum excitation and emission wavelengths were proposed on the basis of maximum difference of Relative Fluorescence Intensity (RFI) between two types of fibers used in the hybrid ECC. Optimum threshold values to discriminate two types of fibers using statistical tools were also proposed. Finally, images of four types of fibers obtained using a fluorescence microscope are compared.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.14
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• pp.5959-5964
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• 2014

Background: Dietary carbohydrate, fiber and sugar intake has been shown to play a role in the etiology of breast cancer, but the findings have been inconsistent and limited to developed countries with higher cancer incidence. Objective: To examine the association of premenopausal and postmenopausal breast cancer risk with dietary carbohydrate, fiber and sugar intake. Materials and Methods: This population based case-control study was conducted in Malaysia with 382 breast cancer patients and 382 controls. Food intake pattern was assessed via an interviewer-administered food frequency questionnaire. Logistic regression was used to compute odds ratios (OR) with 95% confidence intervals (CI) and a broad range of potential confounders were included in analysis. Results: A significant two fold increased risk of breast cancer among premenopausal (OR $Q_4$ to $Q_1$=1.93, 95%CI: 1.53-2.61, p-trend=0.001) and postmenopausal (OR $Q_4$ to $Q_1$=1.87, 95%CI: 1.03-2.61, p-trend=0.045) women was observed in the highest quartile of sugar. A higher intake of dietary fiber was associated with a significantly lower breast cancer risk among both premenopausal ($ORQ_4$ to $Q_1$=0.31, 95%CI: 0.12-0.79, p-trend=0.009) and postmenopausal ($ORQ_4$ to $Q_1$=0.23, 95%CI: 0.07-0.76, p-trend=0.031) women. Conclusions: Sugar and dietary fiber intake were independently related to pre- and postmenopausal breast cancer risk. However, no association was observed for dietary carbohydrate intake.

• Journal of the Korean Applied Science and Technology
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• v.31 no.4
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• pp.679-687
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• 2014

In this study, a new paint which is able to resist the cavitation erosion is tried to be developed by using urethane added with nano particles such as multi-wall and single-wall carbon nano tube and spherical and fiber type graphite. The new paint synthesized was characterized with physical properties and resistivity to cavitation erosion($t_{50}$). Among nano particles, fiber type graphite($t_{50}$ 292min) showed high hardness and wear resistance compared with spherical type($t_{50}$ 182min). For carbon nano tube, single-wall type($t_{50}$ 286min) was higher than multi-wall type in wear resistance. Fiber-type graphite was the best nano-particle for paint with resistivity to cavitation erosion. In the application test of paint, the manually painted sample showed surface with smooth but the surface of sample prepared with spray was not smooth. During spray, dust was fixed on the surface.

• Korean journal of food and cookery science
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• v.9 no.2
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• pp.82-87
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• 1993

This experiment was carried out to determine the total dietary fiber content and free sugar, fatty acid, amino acid compositions in bamboo shoot, lotus root and burdock. Bamboo shoot contained 3.05% of proteins, 0.48% of lipids, 2.45% of fibers, which were larger than those of other samples (lotus root and burdock). Burdock contained more sugars than the others as 18.64%. On a dry matter basis, total dietary fiber by Prosky AOAC method were 62.5% for bamboo shoot, 17.9% for lotus root and 41.9% for burdock. Therefore, the content of dietary fiber in bamboo shoot was the most abundant among them. Free sugar contents (glucose, fructose and sucrose) of the sample were analyzed by HPLC. Sucrose was the most abundant in both bamboo shoot and lotus root, and the content of fructose and sucrose in burdock were almost same. The major fatty acids in bamboo shoot, lotus root and burdock analyzed by GC were palmitic and linoleic acid. Also, linolenic acid were abundent only in bamboo shoot. The results of amino acid analysis showed that aspartic acid, glutamic acid and Iysine were the most abundent amino acids in the sample. Bamboo shoot contained large percentage of protein, the sweet-tasting amino acids and lipid than the other samples. Therefore bamboo shoot can be used as a flavor material because they contain plenty of the sweet-lasting amino acid and free sugar. Bamboo shoot and burdock can be used as potential source of dietary fiber because of the high content of dietary fiber in those samples.

• Journal of Adhesion and Interface
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• v.5 no.1
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• pp.21-28
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• 2004

In this work, glass fiber/nylon 6 and woven glass fiber/nylon 6 composites have been fabricated using glass fiber reinforcements sized with 3-chloropropyltrimethoxysilane(CTMS) having a chloropropyl organo-functional group in the molecular chain end. The interfacial shear strength of glass fiber/nylon 6 composite was measured using a single fiber microbonding test and the interlaminar shear strength and the storage modulus of woven glass fabric/nylon 6 composites were measured using a short-warn shear test and a dynamic mechanical analysis, respectively, informing the effect of the concentration of CTMS on the properties. With increasing CTMS concentration, the interfacial properties of the composites were improved. The results on the interfacial shear strength, interlaminar shear strength, interlaminar failure pattern, and storage modulus with varying the CTMS concentration agree with each other.

• PNF and Movement
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• v.14 no.2
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• pp.131-137
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• 2016

Purpose: The purpose of this study was to compare muscle activities in the frontal plane and scapular plane of the middle fiber and lower fiber of the trapezius muscle at different shoulder abduction angles. Methods: Twenty male and female students in their 20s participated in this study. Each subject maintained shoulder abduction at $75^{\circ}$, $90^{\circ}$, $125^{\circ}$, and $160^{\circ}$ in a standing position and repeated motions three times each in the frontal plane and the scapular plane. While maintaining the motions for 10 seconds in each posture, surface electromyography (EMG) was used to measure muscle activity of the middle fiber and lower fiber of the trapezius muscle. The collected EMG data were normalized using maximal voluntary isometric contraction (MVIC). Differences in muscle activity of the middle fiber and lower fiber of the trapezius muscles according to the angles at each plane were statistically processed using repeated measured analysis of variance, and an independent t-test was used to examine the differences between the two planes at each angle. Results: Muscle activity of the middle and lower trapezius during shoulder abduction in the frontal plane and scapular plane significantly increased as the angles increased (p<.05). However, muscle activity of the middle trapezius was significantly lower in the scapular plane than in the frontal plane for all shoulder abduction angles (p<.05). Conclusion: The results of this study suggest that during shoulder abduction, angles should be different according to the goals, and for training during an acute phase or early phase for functional recovery, it is more efficient to perform the training in the scapular plane than in the frontal plane.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.3
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• pp.396-403
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• 1995

Eightly nine common Korean foods were analyzed by the enzymatic-gravimetric method developed by Prosky et al. and adopted by AOAC to determine total dietary fiber(TDF) content. The average TDF content of the foods analyzed was 4.78${\pm}$3.55% for cereal and grain products, 2.56${\pm}$1.65% for potatoes and starches, 1.94${\pm}$0.77% for sugar and sweets, 10.81${\pm}$6.57% for pulse and pulse products, 9.70${\pm}$5.92% for nuts and seeds, 15..38${\pm}$15.76% for seasonings, and 4.98${\pm}$4.35% for beverages. The foods containing the highest TDF values in the food groups were whole grain barley(17.88%) in cereals, yellow soybean(21.05%) in pulses, black sesame(21.34%) in nuts and seeds, and red pepper powder(39.37%) in seasonings except San Cho powder(52.43%). TDF content of rice, the main staple food of Korea, was 2.75% for brown rice and 0.96% for well-milled rice. The TDF value of the foods analyzed ranged from 0.12 to 23.4 times that fo crude fiber reported in the Korean food composition tables. When we consider dietary fiber contents of foods and food consumption patterns together, it is recommended to consume brown rice instead of well-milled rice and increase the consumption of minor cereals and pulses to raise dietary fiber intake.